Candling--Do chicks move less as they get bigger inside the shell?

Recent candling (day 13 to day 15) shows definite growth, but there seems to be less movement of the embryo. Only 2 out of 6 showed definite movement. Is this normal? Do the chicks get cramped in there? My wife says that's what it was like for her with our kids.
Thanks

I am new at hatching too !! I didnt see any movements too ! I did the float test and they did not wiggle at all ! I thought I lost hope, so I left them alone just in case, before we know it we got 4 healthy silkie cross!! best if you watch your temperature and humidtiy levels you will do fine..